What is the strategy of putting all a country's resources toward a war?
A. Guerilla warfare
B. Naval warfare
C. Total warfare
D. Trench warfare

theredhead1617 is right and these are the reasons why:
(A) guerilla warfare just involves a different style of warfare -- striking with small numbers against a superior enemy, often covertly and under cover. (B) is a different style as well, just war on the waves. And (D) is a tactic in warfare using trenches as cover from enemy fire which was a major feature of battles in WW1.